...
to
The email address where the message is sent. (Required: if no register_form_confirmation 'to' is specified)
This can be:
A string containing one email address, or multiple comma-separated email addresses.
An array containing strings of individual email addresses.
subject
The subject that is used for the email sent to the email filled in at to
. (Not required, default: 'Message sent from %{site}
')
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